https://archive.org/details/648PTK648PVServiceData194748/page/n15/mode/2up
RCA 648PTK, 648PV Television Service Data : Radio Corporation of America : Free Download, Borrow,...
RCA 648PTK, 648PV Television Service DataChassis No. KCS 24A-1, KRS 20-1, KRS 21A-1, KRK-1A, RL-121A. RS-123B1947, 1948
radio corporation of america